Evaluation of phase transformation behaviors of zeolite and antibacterial properties against Gram‐positive and ‐negative bacteria

Abstract

This study deals with the synthesis of zeolite from natural kaolinite using hydrothermal treatment and evaluation of its phase transformation behaviors. The synthesized zeolites were modified with silver ion by using the ion exchange method for the enhancement of antibacterial properties. The characterizations were performed by using X-ray diffraction spectroscopy, Fouriertransform infrared spectroscopy, field emission scanning electron microscopy, and energy-dispersive X-ray. Disk diffusion technique (DDT) was used for the evaluation of the antibacterial property of the modified zeolites. This study observed the transformation of kaolinite into amorphous metakaolin after calcination treatment at 900 C and the successful reconstruction of amorphous metakaolin into synthesized crystal zeolite in the presence of sodium hydroxide as an activating agent. It was also found that the zeolite type A was produced at 100 C, while sodalites were produced at 120 and 140 C. DDT analysis revealed that the modified zeolites showed significant antibacterial capability against Escherichia coli ATCC 11229 and Staphylococcus aureus ATCC 6538. In general, the present study has proven that the zeolites can be synthesized from natural material and can be modified with silver ion to enhance their antibacterial activity.

Antibacterial Activity of Amine-Functionalized Silver-Loaded Natural Zeolite Clinoptilolite

“…From the trend, CS150 with a high amount of Ag-loaded clinoptilolite (150% of the CEC of the Cli) showed the highest antibacterial activity. Thus proving that the antibacterial activity of the modified zeolite was contributed by the Ag [14]. Furthermore, this sample (CS150) had higher antibacterial activity than CS40 which had a lower Ag amount loaded Cli.…”

Green and low-cost synthesis of zeolites from kaolin: a promising technology or a delusion?

“…Kaolinite is already an ideal raw material with the same Si/Al ratio, and quartz only reduces the relative crystallinity of the zeolite, 54 contaminates the product or dissolves. 23,121,122 On the contrary, in the synthesis of zeolites with a higher Si/Al ratio, quartz, provided it dissolves, can be an additional source of SiO 2 . 61,123 Mohiuddin et al have reported that quartz deposits on the surface of ZSM-5 during the synthesis and acts as a promoter in the oligomerisation of hexene-1.…”